apo-wiki

3.5m

Anonymous (anonymous@undisclosed.example.com) — 2026-01-30T05:45:12+00:00

Telescope information The ARC 3.5m telescope is controlled using the TUI software, which is software written in Python using a Tk graphical interface. The telescope can also be controlled with command line commands and scripts, which can be run through TUI. TUI includes some built-in scripts, but users can also provide their own.

a2020

Anonymous (anonymous@undisclosed.example.com) — 2022-03-10T22:54:41+00:00

The Decadal Survey on Astronomy and Astrophysics (Astro2020) got underway in early 2019 with the submission of community white papers. There were two deadlines: one in March for science white papers, and one in July for Activities, Projects, or State of the Profession Consideration (APC) white papers. We submitted a white paper in response to the APC call, arguing for the continued need and relevance of 4-meter class telescopes. Ours is one of ~ 330 APC white papers (+ more than 600 science whi…

aas

Anonymous (anonymous@undisclosed.example.com) — 2022-12-06T18:35:27+00:00

Planning information for AAS 241 08-12 January 2023 Seattle, Washington Meeting web site: Spreadsheet to indicate APO-related talk, poster, booth participation: APO logo for poster or talk usage:

arces

Anonymous (anonymous@undisclosed.example.com) — 2026-01-30T04:34:52+00:00

ARC Echelle Spectrograph (ARCES) The ARC echelle was constructed for the 3.5m at the University of Chicago in the 1990s. ARCES instrument manual on APO website Features / issues * the traces and ThAr lines can move around over the course of a night. The reason has never been completely understood.

arctic

Anonymous (anonymous@undisclosed.example.com) — 2026-01-30T05:03:53+00:00

ARCTIC ARCTIC is an optical imager built at the University of Washington and APO. A wide set of filters in available. These include a diffuser, which can be used in a rotating wheel to provide diffused images to allow for high-precision photometry of bright sources, although the diffuser rotation mechanism has been a challenge to get to work reliably.

bog

Anonymous (anonymous@undisclosed.example.com) — 2022-12-06T17:18:02+00:00

The ARC Board of Governors meetings are held in November. At that meeting the 3.5m Director provides an annual summary of 3.5m-related activities and initiatives. Some recent Science Highlights and Telescope Impact reports are provided below. 2022:

dawg

Anonymous (anonymous@undisclosed.example.com) — 2022-03-10T22:54:02+00:00

Data Reduction Tools Longslit blazeR300.py -- auto reduction routine in PyRAF, originally written by Kevin Covey, modified by Sarah Schmidt, and customized by Adam Kowalski for his PhD thesis. Used to reduce DIS spectra automatically from bias subtraction through flux calibration. Can easily be modified so all tasks run without interactive IRAF pop up windows.

dis

Anonymous (anonymous@undisclosed.example.com) — 2022-03-11T00:09:20+00:00

DIS information/tips Variation of line positions with rotator position (Bill Ketzeback / bketzeback at apo.nmsu.edu) Here is a link to some (from 2006) tests that show line position varies with rotator angle. Here the high resolution gratings refers to the B1200/R1200 pair but the low/med naming convention was likely referring to the older B300/R300 pair not the current B400/R300 set.

eag20200429

Anonymous (anonymous@undisclosed.example.com) — 2022-03-11T16:44:32+00:00

Minutes from Echelle Advisory Group Zoom Meeting on Wednesday April 29, 2020, 10:00-11:00 MDT Attendees: Nancy Chanover (in and out due to poor internet connectivity - SORRY!), Ben Williams, Sarah Tuttle, Kal Kadlec, John Wisniewski, Kevin Schlaufman, Derek Buzasi, Yuta Notsu, Candace Gray, Charli Sakari, Brett Morris

instruments

Anonymous (anonymous@undisclosed.example.com) — 2026-01-30T05:52:50+00:00

Instrument upgrades / New instruments Fiber feed from 3.5m to SDSS/APOGEE White Paper: NETWORKED ASTRONOMY AT APACHE POINT OBSERVATORY ABSTRACT We propose to initiate a project to implement a fiber optic network at Apache Point Observatory such that the existing (and future) spectrographs on site can be supplied with target light from any of four telescopes. The first phase of this implementation will be to develop the site infrastructure to connect all of the telescopes through the addition…

kosmos

Anonymous (anonymous@undisclosed.example.com) — 2026-05-06T22:52:28+00:00

KOSMOS The Kitt Peak Ohio State Multi-Object Spectrograph (KOSMOS) was loaned to ARC by NOAO for use on the 3.5m telescope. Because the KOSMOS instrument was modified from its original state in order to be installed on the ARC 3.5m telescope at APO, we now refer to this instrument as KOSMOS II.

newechelle

Anonymous (anonymous@undisclosed.example.com) — 2022-03-11T16:43:58+00:00

Background The ARC Echelle Spectrograph (ARCES) continues to be a popular and scientifically productive instrument among the users of the 3.5m telescope. Recent instrument usage statistics are below: Year ARCES Usage (%) 2019 26.7 2018 33.9

newspectrograph

Anonymous (anonymous@undisclosed.example.com) — 2022-03-10T22:11:04+00:00

New Spectrograph Information [raw-attachment:NewDISproposal.pdf NewDIS Proposal (9/15)] New Spectrograph Science Drivers and Capabilities Other Instruments Spreadsheet of other instruments Final Report of the New Spectrograph Committee: [raw-attachment:APO-NSC-FinalReport.pdf]

nicfps

Anonymous (anonymous@undisclosed.example.com) — 2026-01-30T06:06:18+00:00

NICFPS NICFPS is a near-IR imager built at the University of Colorad. It was originally going to have Fabry-Perot mode (hence the FPS), but this has not been implemented NICFPS instrument manual on APO website Features / Issues Data reduction * IRAF-based alternatives * NICFPS data reduction routines in IRAF from Misty Bentz (Georgia State) can be found

satellites

Anonymous (anonymous@undisclosed.example.com) — 2025-04-01T15:44:59+00:00

This page is intended to provide updates concerning the impact of constellations of satellites on observing from the ARC 3.5m at APO. Last updated: April 1, 2025 (NJC) The observatory has received relatively little feedback concerning this issue. However, one observer (Anne Verbiscer, University of Virginia) reports having had some of her data contaminated by satellite streaks, primarily when observing with ARCTIC close to twilight. She provided this gallery of images to demonstrate the effec…

spicam

Anonymous (anonymous@undisclosed.example.com) — 2022-03-11T16:45:30+00:00

SPICAM

spm19

Anonymous (anonymous@undisclosed.example.com) — 2022-03-10T22:55:12+00:00

The Strategic Planning meeting was held on June 11-12, 2019 in Sunspot, NM. A link to the meeting website is here: A link to the detailed meeting minutes is here:

start

Anonymous (anonymous@undisclosed.example.com) — 2026-03-27T19:33:09+00:00

Welcome to APO Users Wiki This is a site to allow APO users to share information about using APO facilities, in particular, the ARC 3.5m telescope and its instruments. Users are encouraged to share information about instrument/telescope performance, data reduction, etc. through this wiki.

tdawg

Anonymous (anonymous@undisclosed.example.com) — 2022-03-10T22:52:43+00:00

The Time Domain Astronomy Working Group was established in June 2017 with the goal of examining the current and future role that the ARC 3.5m telescope at APO can play in the rapidly emerging field of time domain astronomy. The TDAWG was chaired by Deputy Director Ben Williams and had the following charge:

tewg

Anonymous (anonymous@undisclosed.example.com) — 2022-03-10T22:53:30+00:00

The Training and Education Working Group was established in March 2018 with the goal of examining the use of the 3.5m telescope at APO for student training and education The TEWG was chaired by Erica Ellingson of the University of Colorado and had the following charge:

triplespec

Anonymous (anonymous@undisclosed.example.com) — 2026-01-30T04:57:20+00:00

TRIPLESPEC Triplespec is a near-IR spectrograph, constructed at the University of Virginia. Other versions of the instrument have been used at the Palomar 200-inch and the SOAR telescope. Triplespec provides spectra in 5 orders, with a slit-length of 43 arcsec

userscommittee

Anonymous (anonymous@undisclosed.example.com) — 2026-02-05T18:17:42+00:00

Users' Committee Information and Meeting Minutes The ARC 3.5m Users' Committee plays an important role in representing the interests of the broad user community. Each institutional member of ARC (including leasing partners) has a Users' Committee (UC) representative who participates in monthly teleconferences. The UC representatives serve as a conduit of information - both from the users to the management team as well as from the management to the users. The current (2025) UC representatives …